Ready built mic switch units are available, but none that I looked at really suited my needs, thus the idea to design and construct a custom solution formed.
The cause of the damage to these resistors appeared to be from over enthusiastic use of RF power being put into the linear. Obviously, with one resistor hanging on for dear life by only one of it’s leads, it’s needless to say, the linear wasn’t working.
After short consideration, I came to the conclusion that the asking price was a bit too high to take a risk on a partially working radio. Within a matter of days, I had been sent details of the radio from two different people, the second time the asking price had been reduced from the original price.
As standard the Kenwood TS-2000 is shipped with an amber display, while the backlights for the keys are green in colour. This how-to shows you how to change the amber display to almost any colour you want. Colour options are only limited by the LED’s available.
As with any mod or repair, if you’re not confident working with SMD components, don’t attempt the work, making a mistake could result in a ruined radio. Doing this mod will void any warranty you have.
The Cobra 200 GTL-DX has a built-in talkback function. Some models allow switching this function on or off as desired, others have the ability to adjust the volume. This particular version of the Cobra 200 GTL-DX has a fixed volume, which the customer doesn’t want.
Luckily, the service manual has details for a mod to adjust the preset level of the talkback function. The mod simply comprises of changing the value of a single resistor, in this case R109. The resistor is a 33K ohm SMD device, and located in a quite densly populated area of the PCB.
There are many complaints concerning the audio quality and/or volume when using a standard Yaesu MH31 microphone. This particular microphone is shipped with a lot of radios as standard. This mod is described elsewhere online, however this is my attempt at improving the MH31.
The unmodified microphone uses a cheap dynamic element, which is placed behind a cotton wool type pad to keep moisture and dirt out, also the hole in the front of the mic serves to reduce sound entering the mic even more!